Fluid proportioner means

ABSTRACT

A fluid proportioning system for obtaining desired mixtures of fluids has at least two fluid inlet conduits with each of said conduits carrying a flow meter and flow control means. A common conduit interconnects the inlet conduits and leads to an automatic fluid supply control valve means for permitting passage of fluid in the common conduit at a predetermined pressure and cutting off fluid flow at a second predetermined pressure. A surge tank is interconnected with the automatic fluid supply control valve means for receiving fluid from the common conduit and an output conduit delivers fluid from the surge tank. Preferably the automatic supply control valve means is a mechanically operated pressure valve circuit which has an inlet means for admitting fluid flow and an outlet means for delivering fluid from the inlet means. Valve means permits fluid flow from the inlet means to the outlet means in a first position of the valve means and cuts off fluid flow from the inlet to the outlet means in a second position. A fluid pressure sensitive means controls the valve means to make it automatically responsive to a buildup in pressure at the outlet means to shift from the first to second position and automatically responsive to a lowering of pressure in the outlet means to cause the valve means to shift from the second position to the first position.

United States Patent Berger [451 July 18, 1972 [54] FLUID PROPORTIONERMEANS James E. Berger, 124 Second Avenue, Newton, Mass. 02194 [22]Filed: March 16,1970

[21] Appl.No.: 19,771

[ 72] Inventorz [52] U.S. Cl ..l37/606, 92/76, 137/492.5

[51] Int. Cl ..F16k 31/12 [58] Field olSearch ..137/88,607, 115,116.31,117, 137/488, 492, 492.5, 606

[56] References Cited UNITED STATES PATENTS 3,032,053 5/ 1962 Ross et al..137/607 X 2,624,980 1/1953 Hughes 37/117 X 3,298,383 1/1967 Cooper137/88 X 3,347,256 10/1967 Massey et al.. 137/115 3,534,753 10/1970Ollivier 137/88 X 2,799,996 7/1957 Van Meter.. .....60/52 S 3,570,5193/1971 Bianchetta ..137/101 Primary Examiner-M. Cary Nelson AssistantExaminer-David J. Zobkiw Attorney-Wolf, Greenfield & Sacks 57] ABSTRACTA fluid proportioning system for obtaining desired mixtures of fluidshas at least two fluid inlet conduits with each of said conduitscarrying a flow meter and flow control means. A common conduitinterconnects the inlet conduits and leads to an automatic fluid supplycontrol valve means for permitting passage of fluid in the commonconduit at a predetermined pressure and cutting off fluid flow at asecond predetermined pressure. A surge tank is interconnected with theautomatic fluid supply control valve means for receiving fluid from thecommon conduit and an output conduit delivers fluid from the surge tank.Preferably the automatic supply control valve means is a mechanicallyoperated pressure valve circuit which has an inlet means for admittingfluid flow and an outlet means for delivering fluid from the inletmeans. Valve means permits fluid flow from the inlet means to the outletmeans in a first position of the valve means and cuts off fluid flowfrom the inlet to the outlet means in a second position. A fluidpressure sensitive means controls the valve means to make itautomatically responsive to a buildup in pressure at the outlet means toshift from the first to second position and automatically responsive toa lowering of pressure in the outlet means to cause the valve means toshift from the second position to the first position.

1 Claim, 5 Drawing Figures PATENTEU JULIE m2 3,677,296

SHEET 1 0F 3 FIG.

INVENTOR JAMES E. BERGER ATTORNEYS PATENTED JUL 1 8 I972 V '4. LI"

SHEET 3 OF 3 I a I E 2 a (\l (D 2 rat \g v o LO 0 O 4.1 -5 \i/ (D o y: 9L LL mm x INVENTOR JAMES E. BERGER ATTORNEYS BACKGROUND OF THE INVENTIONA large number of gas proportioning systems, i.e., systems for providinga predetermined mixture of two or more gases, are known in the art.Often such gas proportioners are electrically operated or regulatedmaking their usage in certain field or other operations complicatedbecause of the need for an electrical supply.

It is an object of this invention to provide a fluid proportioner forproperly mixing two or more fluids in a predetermined proportion whichpredetermined proportion can vary as desired.

Another object of this invention is to provide a gas proportioner inaccordance with the preceding object which does not require the use ofelectric power.

Another object of this invention is to provide a gas proportioner inaccordance with the preceding objects which can be easily constructedand which requires little or no maintenance over long periods of time.

Still another object of this invention is to provide an'automatic fluidsupply control valve circuit sensitive to fluid pressure andautomatically operable without the need for electric power.

It is a feature of this invention that the gas proportioners do not havean explosion hazard since no electric power need be used. Other featuresinclude ease of operation by unskilled personnel, the lack of anyminimum gas flow requirement and automatic operation once an initialratio of gases to be mixed isset up. Any number of gases or other fluidscan be blended by the systems of this invention. Inexpensive reading,recording and. adjustment instruments can be incorporated in thesystems. The systems can be designed for a wide range of capacities andgas pressures. High tolerances with good precision are obtained. Bypassvalves can be used to allow purging and sampling during ordinaryoperation. Permanent calibration can be obtained and the systems arehighly versatile in that it is relatively simple to change the ratio ofany gas or liquid mixture to suit different applications.

BRIEF DESCRIPTION OF THE INVENTION A fluid proportioning system forobtaining desired mixtures of fluids comprises at least two fluid inletconduits each having a flow meter and flow control means. A commonconduit interconnects the fluid inlet conduits and leads to an automaticfluid supply control valve means for pennitting passage of fluid in saidcommon conduit at a predetermined pressure and cutting off fluid flow ata second predetermined pressure. A surge tank interconnects with theautomatic fluid supply control valve means for receiving fluid from thecommon conduit. An output conduit delivers the fluid from the surge tankpreferably at a predetermined pressure.

Preferably an automatic fluid supply control valve means comprises inletmeans for admitting a fluid flow and outlet means for delivering fluidfrom said inlet means. Valve means permit fluid flow from the inletmeans to the outlet means in a first position of the valve means andcuts off fluid flow from the inlet to the outlet means in a secondposition. A fluid pressure sensitive means controls the valve means tomake the valve means automatically responsive to buildup in fluidpressure at the outlet means to shift from the first position to thesecond position and automatically responsive to a lowering of pressurein the outlet'means to cause the valve means to shift from the secondposition back to the first position. Preferably the fluid pressuresensitive means is mechanically actuated.

BRIEF DESCRIPTION OF THE DRAWINGS The above and other objects, featuresand advantages of the present invention will be better understood fromthe following specification when read in conjunction with theaccompanying drawings in which:

FIG. 1 is a diagrammatic showing of a preferred embodiment of a fluidproportioner of the present invention;

FIG. 2 is a diagrammatic showing of a preferred embodiment of anautomatic fluid supply control valve means useful therein;

FIG. 3 is a second diagrammatic showing of the control valve systemmeans in a second position; and

FIGS. 4 and 5 are diagrammatic showings of side and top viewsrespectively of an element of the system of FIGS. 2 and 3.

DESCRIPTION OF PREFERREDEMBODIMENTS With reference now to the drawings,a preferred embodiment of a fluid proportioner system is illustratedgenerally at in FIG. 1 and comprises a supply and mixing section ll, anautomatic supply control valve system 12, a surge tank storage means 13,an output section 14 and a purging section 15. The gas proportionersystem 10 is set up to mix and regulate two gases such as argon andhelium which may be supplied at the same or different pressures andwhich are blended, stored in a surge tank 13 and passed out of thesystem through an output at a constant pressure to a user device (notshown) requiring the uniform mixture of gases at a constant pressure.

The supply and mixing section 11 of the preferred embodiment providesfor mixing of two gases although three or more gases can be mixed byduplicating the elements leading to the common conduit as desired.

The supply and mixing section 11 comprises two gas inputs l6 and 17, twoinlet conduits l8 and 19, both of which meet at a T connection supplyinga common duct or conduit 20. Along each of conduits l8 and 19 arepositioned a fluid regulator 21 and 22 preferably having attached visualinput gauges 23 and 24. Next in line in the conduits l8 and 19 areconventional flow meters 25 and 26 respectively followed by flow adjustmeans such as needle valves 27 and 28.

The common duct 20 leads to the automatic supply control valve system 12as will be more fully described and from there through a conduit 30 tocheck valve 31 which prevents backflow of gas. In some cases, checkvalves can be provided in conduits l8 and 19 just before the common ductor in the common duct with the check valve 31 eliminated. Conduit 32leads the gas to a storage surge tank 13 preferably having aconventional gas pressure gauge 33 connected in the line to determinethe pressure of any gas in the surge tank when desired. A conduit 34leadsto a conventional line regulator 35 having a conventional pressuregauge 36 attached thereto and from thence to the output 14.Interconnected by conduits, with the common duct 20 and conduit 34, is amanually operated three-way bypass valve 40 having an atmospheric output41 useful in purging the system and setting up a desired flow as will bedescribed.

The flow meters, needle valves, gauges, line regulators, check valve andtanks are all of conventional design with many substitutes possible.Similarly, the automatic supply control valve system can be any controlvalve system which permits passage of gas when the gas pressure in line30 and consequently surge tank 13 falls below a predetermined value suchas pounds per square inch and which shuts ofl gas flow to the surge tankwhen the pressure in tank 13 and conduit 30 reaches a predeterminedvalue such as pounds per square inch. These values can be varied greatlydepending upon the particular conditions to be met.

In the preferred embodiment, the input connections 16 and 17 areconnected to predetermined gas supplies to be mixed. For example,connection 16 can be connected with an argon gas supply at 200 p.s.i.g.with input 17 connected to a helium gas supply at 150 p.s.i.g. Lineregulators 21 and 22 are adjusted to provide p.s.i.g. in each of theconduits l8 and 19 beyond the regulators. Flow meters 25 and 26 of aconventional type provide for visual scanning of the flow rate inconduits l8 and 19 with manually operated needle valves 27 and 28permitting adjustment of the flow rate as desired to obtain desiredproportions. The gases move along lines 18 and 19 in the direction ofarrow 60. The gases are mixed by flow turbulence when they pass throughthe Tconnection into the common conduit 20. Ifthe purging valve 40 isclosed, the common conduit carries the mixed and blended gases to theautomatic supply control valve means which automatically stops gas flowif the gas, pressure in line 30 and surge tank 13 is above 120 p.s.i.g.Check valve 31 prevents backflow of gas from the surge tank 13. Thesurge tank 13 acts as a gas storage means and is constantly maintainedat a pressure of the mixed gases within the range of from 80 to 120pounds per square inch due to the action of the automatic supply controlvalve system 12. When the output connection is opened, the lineregulator 35 pennits flow of gas toward the output from thesurge tank atpressures below 75 p.s.i.g. As the pressure in the surge-tank drops, toa value below 80 p.s.i.g., the automatic supply control valve opens torefill the tank.

The purge valve 40 is used to purge the system at the end of operation,or at the beginning of operation to permit adjustment of the needlevalves and purging of the system. After the proper gas ratios have beenset up at the start, bypass valve 40 is closed during normal operation.

Preferably, none of the elements in the system 10 are electricallyoperated, therefore, the system is automatically operated by the .gaspressures involved once initial start up is made.

The automatic supply control valve system 12 is best illustrated inFIGS. 2 and 3 with the system comprising a mechanical pressure actuator70, a pilot valve 80, a main gas valve 81,

' a check valve 82, and a snubber 83 interconnected by suitable conduitportions 84, 85, 86, 87,88 and 89 as shown in FIGS. 2

and 3.

In the preferred embodiment, the gas line of the common conduit 20introduces the mixed gases to lines 84, 85 and the inlet of aconventional spring biased two-position, normally closed, spool valve 81having an open position as shown in FIG. 2 and closed position as shownin FIG. 3 with a conventional shuttle valve spool member controlling thepositions. Arrows shown in FIGS. 2 and 3 indicate gas flow in the openand closed position of valve 81. v

The gas passes in the direction of arrows shown in FIG. 2 when the spoolvalve 81 permits flow to conduit 30 with some of the gas being directedto a pilot pressure'control chamber 90 which balances the bias of aspring 91 to keep the spool in the open position.-Gas from the outletline 30 exerts a pressure in lines 87 and 88 and consequently throughsnubber 83 to a pressure sensitive mechanical linkage or pressureactuator 70 while the gas is stopped from flow toward the valve 80 bythe check valve 82. In the open position, the pilot valve 80 which is athree-outlet, 2-position valve, permits passage of gas to exhaust gasfrom conduit 89 through the check valve 82 while preventing flow of gasfrom the line 84 into the line 89. As can be seen from the drawing, thespool valve is in an opened flow position only when sufficient gaspressure exists in the chamber 90 to overcome the bias of the spring 91to a sufficient degree. In the preferred embodiment, the spool valve isadjusted so that a minimum gas pressure of 80 p.s.i. is required topermit flow through the valve 81.

The pressure sensitive actuator 70 of the preferred embodiment isselected so that when the gas pressure in line 87, corresponding to thegas pressure in outlet line 30; builds up beyond a value of 120p.s.i.g., the actuator 70 will move a trip arm 92 to its extendedposition to trip the switching mechanical member 93 of valve 80 asshown, to the position shown in FIG. 3. Conversely, when line pressurein outlet line 30 falls below 80 p.s.i.g., the trip arm 92 moves to itswithdrawn position to permit gas flow to the surge tank.

In the position shown in FIG. 3, valve 80 permits gas passage betweenconduits 84 and 89 so that the gas pressure in the line.20 issuperimposed over the spring pressure provided by spring 91 to move thespool of valve 81 and close the valve 81. Since valve 80 in thisposition does not permit flow to line 88, gas flow is cut off to theoutlet line 30.

A preferred mechanical pressure sensitive actuator issemidiagrammatically illustrated in FIGS. 4 and 5 where valve 80, line87 and snubber 83 are shown. The actuator 70 has a gas pressure cylinderconnected to line 87 with a double ended piston 101 connected to anactuator arm 103 by a linkage 102. Ann 103 is pivotally mounted on a rod104. A bumper arm 105 is also pivotally mounted on rod 104 for arcuatemovement about the rod. Stops 106 and 107 provide a set of limit or stopsurfaces 108 and 109 for the actuator arm 103 and limit or stop surfaces110 and 111 for bumper arm 105. A compression spring 112 isinterconnected with free ends of arms 103 and 105. The trip arm. 92 isspring biased to its withdrawn position by a spring (not shown). Highpressure cut off compression spring 113 and low pressure cut offcompression spring 114 are provided and are manually adjustable throughthreaded bolts 115 and 116 respectively. Spring 114 is attached to oneend of piston 101 at one head 101A. The low pressure position of thepiston head 101A and springs is shown in dotted outline in FIG. 5. Themechanical actuator thus comprises first means 101 for reciprocallymoving in response to high and low pressure conditions. The springs 1 15and 116 comprise means for determining the high and low pressureconditions.

In operation, the reciprocal piston 101 is prevented from moving aspressure builds up in line 87 by high pressure spring 1 13 until apressure of almost 120 p.s.i.g. is reached in line 87. When the pressurereaches 120 p.s.i.g., the piston moves to the position shown in FIGS. 4and 5. As the pressure is reduced in line 87, spring 114 preventsmovement until the pressure drops to about 80 p.s.i.g. whereupon piston101 and arm 103 move in the direction of arrows 120 and 121. Shortlybefore arm 103 reaches the stop surface 109, the force of compressionspring 112 snaps arm 105 to its inactive position shown in dottedoutline in FIG. 4 against stop surface 110. The snap action occurs whenthe attachment point of spring l12on arm 103 passes beyond a pointvertically beneath the attachment point of spring 112 on arm 105. Whenarm 105 is thus disengaged, trip arm 92 automatically returns to itswithdrawn position shown in FIG. 2. As gas pressure builds up in line87, low pressure spring 114 prevents activation of trip arm 92 until apressure of 80 p.s.i.g. is reached whereupon arm 102 moves to snap thebumper arm 105 into the position shown in FIG. 4 to extend trip arm 92to its operative position.

It should be understood that other automatic supply control valvesystems can be used in the gas proportioner of this invention.Similarly, other pressure sensitive actuators and mechanical linkagescan be used as known in the art. The automatic supply control valvemeans of this invention can be used in other systems to start and stopfluid flow as desired as in liquid systems or gas systems of all types.

Many variations are possible in the present invention. For example, themain gas valve 81 can comprise a number of different types of valvesincluding a valve which allows elimination of line 85 and the chamber90. In this embodiment, a twoposition main gas spool valve is used withthe spool automatically on (allowing gas flow to conduit 30) untilactuated by the mechanical linkage 92 so that pressure exerted in line89 moves the spool to a closed position.

What is claimed is:

1. A fluid proportioner for obtaining a mixture of fluids comprising,

at least two fluid inlet conduits,

each of said inlet conduits having a flow meter and flow control means,

a common conduit interconnecting said inlet conduits and connecting withan automatic fluid supply control valve means for permitting passage offluid at fluid pressures below a first predetermined low pressure andcutting off fluid flow at a second predetermined pressure higher thansaid first pressure,

said fluid supply control valve means comprising a mechanical actuatorresponsive to said first fluid pressure and said second fluid pressurefor permitting and cutting off fluid flow respectively,

a surge tank interconnected with said automatic fluid supply controlvalve means for receiving fluid from said common conduit through saidautomatic fluid supply control valve means, said first and secondpressures being sensed between said automatic fluid supply control valvemeans and said surge tank,

7 a tank outlet means for delivering fluid from said tank,

a line pressure regulator in said tank outlet means for allowing fluidflow therethrough at a pressure below said second predeterminedpressure,

said mechanical actuator comprising,

first means for moving in response to said predetermined low pressurecondition between said automatic fluid supply control valve means andsaid tank and for moving reciprocally in response to said predetemiinedhigh pressure condition between said automatic fluid supply controlvalve means and said tank,

means for determining said low pressure condition and said high pressurecondition,

a first arm linked to said first means for movement in

1. A fluid proportioner for obtaining a mixture of fluids comprising, atleast two fluid inlet conduits, each of said inlet conduits having aflow meter and flow control means, a common conduit interconnecting saidinlet conduits and connecting with an automatic fluid supply controlvalve means for permitting passage of fluid at fluid pressures below afirst predetermined low pressure and cutting off fluid flow at a secondpredetermined pressure higher than said first pressure, said fluidsupply control valve means comprising a mechanical actuator responsiveto said first fluid pressure and said second fluid pressure forpermitting and cutting off fluid flow respectively, a surge tankinterconnected with said automatic fluid supply control valve means forreceiving fluid from said common conduit through said automatic fluidsupply control valve means, said first and second pressures being sensedbetween said automatic fluid supply control valve means and said surgetank, a tank outlet means for delivering fluid from said tank, a linepressure regulator in said tank outlet means for allowing fluid flowtherethrough at a pressure below said second predetermined pressure,said mechanical actuator comprising, first means for moving in responseto said predetermined low pressure condition between said automaticfluid supply control valve means and said tank and for movingreciprocally in response to said predetermined high pressure conditionbetween said automatic fluid supply control valve means and said tank,means for determining said low pressure condition and said high pressurecondition, a first arm linked to said first means for movement inresponse to movement of said first means, and a second arm linked tosaid first arm by a spring whereby predetermined movement of said firstarm causes snap movement of said second arm at a predetermined positionof said first arm permitting rapid actuation of said second arm at highand low pressure values exerted on said first means.